Device for coupling an evaporator to an expansion valve

ABSTRACT

The invention relates to a device ( 28 ) for coupling a heat exchanger, such as an evaporator ( 10 ), to an expansion valve ( 26 ), in particular for a vehicle, said exchanger and said expansion valve being provided with ports ( 18, 20, 22, 24 ) for the inlet/outlet of fluid, at least one ( 24 ) of the ports of the expansion valve not being aligned with one ( 18 ) of the ports of the exchanger, said device including a first part ( 30 ), intended for being assembled and seemed to the exchanger and/or the evaporator, said first part ( 30 ) being capable of defining, with at least one adjacent part, at least one first fluid passage intended for connecting said non-aligned ports ( 18, 24 ), said adjacent part being selected among a second part ( 32 ) of said device, said exchanger and/or said expansion valve.

TECHNICAL FIELD

The present invention relates to a device for coupling a heat exchanger such as an evaporator to an expansion valve, in particular for a vehicle.

STATE OF THE ART

An evaporator is known, intended for an air conditioning device of the interior of a vehicle, that comprises a bundle formed from a stack of plates allowing for a heat exchange between a flow of air passing through the bundle and a refrigerant circulating in the bundle. The bundle is arranged between two end plates. This type of evaporator is described in the document FR-A1-2 026 437 from the applicant and is well known to those skilled in the art.

One of the end plates of the evaporator comprises two ports respectively for the refrigerant to enter into the evaporator and for this fluid to exit.

It is also known practice to link the evaporator to an expansion valve via a coupling device which is generally formed by a metal block. The expansion valve comprises fluid inlet and outlet ports intended to be linked by internal passages of the coupling device respectively to outlet and inlet ports of the evaporator. The axes of the inlet and outlet ports of the expansion valve are parallel and extend in a plane passing substantially through a bulb of the expansion valve.

In use the bundle of he evaporator is generally arranged vertically and the inlet and outlet ports of the evaporator then emerge horizontally.

In the case where the expansion valve is positioned horizontally and the center distance of the ports of the evaporator is substantially identical to that of the ports of the expansion valve, that does not pose any design problems regarding the coupling device because its internal fluid passages can be rectilinear, which is relatively simple to produce. The document EPA2-1 515 104 describes a coupling of this type.

However, to optimize the operation of the bulb of the expansion valve, it is preferable for it to be in a high position, which means positioning the expansion valve such that the abovementioned plane of its ports is in a vertical position or slightly inclined relative to the vertical. This nevertheless poses a design problem regarding the coupling device. In effect, although one of the passages of the device could be substantially rectilinear to couple aligned ports of the evaporator and of the expansion valve, the other passage is more complex to produce because it has to include one orifice aligned with the port of the evaporator, another orifice aligned with the port of the expansion valve, and a duct linking these orifices. A first solution for producing this duct would be to orient it in an inclined manner and to produce it by drilling into the body inside the block of the device during a machining operation. This would however be complex to implement and would entail overdimensioning the block because or the bends to be formed.

The aim of the present invention is notably to provide a simple, effective and economical solution to this problem.

SUMMARY OF THE INVENTION

The invention proposes a device for coupling a heat exchanger, such as an evaporator, to an expansion valve, in particular for a vehicle, said exchanger and said expansion valve being provided with fluid inlet/outlet ports, at least one of the ports of the expansion valve not being aligned with one of the ports of the exchanger, said device comprising a first part, intended to be joined and fixed to the exchanger and/or the evaporator, said first part being suitable for defining, with at least one neighboring part, a first fluid passage intended to couple said non-aligned ports, said neighboring part being chosen from second part of said device, said exchanger and/or said expansion valve.

The invention makes it possible to simplify the production of the coupling device, in particular when the expansion valve is not positioned horizontally, that is to say that at least one of its ports is not aligned with a port of the exchanger. According to the invention, the duct is in fact formed by making a number of parts cooperate with one another, in particular an parts such as the exchanger and/or the expansion valve. The formation of the duct in the part or parts of the coupling device is thus simplified compared to the production by drilling of a bent passage in the body of a single block.

According to an advantageous embodiment of the invention, said first part is intended to be pressed flat onto the exchanger and comprises through holes intended to cooperate respectively with the ports of the exchanger. Said second part is intended to be pressed flat onto the first part and comprises two through holes intended to cooperate respectively with the ports of the expansion valve. The holes of the parts are further in fluidic communication to define said first passage as well as a second passage intended to couple the other ports of the exchanger and of the evaporator.

It is in fact easy to form through holes in parts, for example by machining, or to form parts directly with holes, for example from casting. The parts of the device are preferably metal, and for example made of aluminum and/or aluminum alloys.

In the present application, the concept of “through holes” should be understood to mean holes which pass through a part, that is to say whose ends emerge on opposite faces of the part, these passages extending preferably in a direction intended to be substantially parallel to the axes of the ports of the exchanger and/or of the expansion valve.

The parts are stacked and fixed together and to the exchanger, for example by brazing. In the assembled position, the holes of the parts define the passages coupling the ports of the exchanger to the ports of the expansion valve. The fact that the first part is pressed flat and fixed onto the exchanger, and for example onto an end plate of this exchanger, makes it possible to close the first passage in a seal-tight manner, on the side of the exchanger. The fact that the second part is pressed flat and fixed onto the first part makes it possible to close the first passage in a seal-tight manner, on the side of said second part. Furthermore, the holes of said parts are linked in seal-tight manner to one another and with the ports of the exchanger and of the expansion valve.

In a preferred embodiment of the invention, the holes of the first part are formed respectively by an opening or slit of elongate form, defining, with said exchanger and/or said second part, said first passage, and by an orifice, defining said second passage.

At least a part of the slit can have an incurved form about en axis of the orifice of the first part. This incurved part can have a radius of curvature, taken substantially at the middle of the slit, which is substantially equal to a center distance between the holes of the second part. This makes it possible to allow the adjustment of the angular position of the second part with respect to the first, about the axis of the orifice of the first part. The angular range over which the incurved part of the slit extends corresponds substantially the angular range of adjustment of position of the second part with respect to the first. This also makes it possible to provide a single reference (called standard part) for said first part, this reference being able to be associated with a number of different references for the second part, the references of the second part being able to differ from one another by the positions of their holes.

The slit can comprise a rectilinear part of which one end is linked to the incurved part of the slit and of which the opposite end is intended to cooperate with a port of the exchanger.

One of the holes of the second part can emerge in the incurved part of the slit of the first part.

The first part can be formed by a plate or a sheet.

In the case where a sheet is used, the latter can be stamped, the sheet comprising at least two indented zones at the bottom of which the holes are formed, for example by drilling.

The second part can be formed by a metal block, and its holes can be formed by orifices.

Said device will be able to comprise tubular bushings into which some of the holes of the second part emerge.

Some of these tubular bushings can protrude on a face of the second part, which is situated on the side opposite the first part, and which intended to be inserted into the ports of the expansion valve. These bushings simplify the assembly and the positioning of the expansion valve on the coupling device.

Others of these tubular bushings can protrude on a face of the second part, which is situated on the side of the first part, and which are intended to be inserted into the holes of this first part. These bushings simplify the assembly and the positioning of the parts on one another.

The present invention relates also to an assembly comprising a heat exchanger such as an evaporator, an expansion valve, and a coupling device as described above.

The present invention relates also to a method tor assembling a device as described above, in which the part or parts are pressed flat and fixed onto one another and/or between said exchanger and said expansion valve, for example by brazing, depending on the desired angular position of the expansion valve.

Advantageously, the second part is positioned in relation to the first part such that one of the holes of the second part is substantially aligned on the axis of a corresponding hole of the first part, the second part being positioned angularly in relation to the first part about the abovementioned alignment axis, to obtain the orientation desired for the expansion valve.

DESCRIPTION OF THE FIGURES

The invention will be better understood and other details, features and advantages of the invention will become apparent on reading the following description given as a nonlimiting example and by referring to the attached drawings, in which:

FIG. 1 is a partially exploded perspective schematic view of an assembly comprising on evaporator, an expansion valve and a device for coupling the evaporator to the expansion valve, according to the invention;

FIG. 2 is a view on a larger scale of the expansion valve and of the coupling device of FIG. 1; and

FIGS. 3 to 6 are views similar to those of FIG. 2 and representing variant embodiments of the invention.

DETAILED DESCRIPTION

Reference is first of all made to FIG. 1 which represents an exchanger 10 of the evaporator type, notably for an air conditioning device of the interior of a motor vehicle. This exchanger 10 comprises, for example, a stack of exchange plates 12 arranged between two end plates 14, 16.

The plates will be able to be grouped in pairs to form a tube allowing a flow of refrigerant between the plates of a some pair of plates. Between two neighboring tubes, said exchanger will be able to comprise separators making it possible to increase the exchange surface area with a flow of air passing through the exchanger by passing between the tubes. Said plates comprise, at at least one of their ends, connection means, such as added-on stamped parts or flanges, forming manifolds making it possible to pass the refrigerant from one pair of plates to the other and emerging at at least one 16 of said end plates.

This latter comprises a fluid inlet port 18 in the exchanger and a fluid outlet port 20 of the exchanger, communicating here with said manifolds. As can be seen in FIG. 1, in the position (vertical) of use of the exchanger, the axes of the ports 18, 20 which are parallel extend in a horizontal plane P1.

The ports 18, 20 of the exchanger 10 are linked to ports 22, 24 of an expansion valve 26 via a coupling device 28 according to the invention.

In the case represented in FIG. 2, the expansion valve 26 is in the vertical position and the axes of its ports 22, 24 are parallel to one another and to the axes of the ports 18, 20, and extend in a vertical plane P2 which passes through a bulb 30 of the expansion valve, which is here in a high position.

The part 22 of the expansion valve 26 is aligned on the port 20 of the exchanger 10 and the port 24 of the expansion valve 26 is not aligned on the port 10 of the exchanger.

The coupling device 20 according to the invention ensures the fluidic communication between the ports 20 and 22, on the one hand, and the ports 18 and 24, on the other hand, and here comprises an assembly or stack of two parts 30, 32.

A first part 30 of the device 28 is pressed flat against the and plate 16 and comprises two through holes 34, 36 fluidically linking to the ports 18, 20 of the exchanger. This part 30 is here formed by a plate of small thickness (for example between 1 and 10 mm) with substantially rectangular outline. The passage of the holes 34, 36 is here produced in a direction parallel to the ports 1B-24.

The hole 34 is formed by a cylindrical orifice aligned on the axis of the port 20 of the exchanger. The hole 36 is formed by a substantially L-shaped slit of elongate form. This slit comprises a first rectilinear and vertical 38, the top end of which is situated facing the port 18 of the exchanger, is in the plane P1, and serves to fluidically link with this port. The rectilinear part 38 is linked by its bottom and to the top end of an incurved part 40 of the slit, the bottom and of which is situated substantially facing the port 24 of the expansion valve, and is in the plane P2. The part 40 is incurved about an axis A which is the axis of the hole 34 and of the port over an angular range of approximately 45° in the example represented. The radius of curvature R of this incurred part 40 is measured between the axis A and the middle of the slit.

When the part 30 is applied and fixed, for example by brazing, onto the end plate 16, the ports 18, 20 are in fluidic communication with the top and of the hole 36 and with the hole 34, respectively. The end plate 16 blocks the rest of the hole 36 in a seal-tight manner, on the side of the exchanger.

The second part 32 of the device is pressed flat against the first part 30 and comprises two through holes 42, 44 fluidically linking to the ports 2, 24 of the expansion valve. This part 32 is here formed by a substantially parallelepipedal metal block that has, for example, a thickness of between approximately 5 and 20 mm. The passage of the holes 42, 44 is here produced in a direction parallel to the ports 18-24. The holes 42, 44 are each formed by a cylindrical orifice. The orifice 42 is aligned on the axis A, that is to say on the hole 34 of the first plate 30 and on the ports 20 and 22. The orifice 44 is aligned on the axis B of the port 24 of the expansion valve and is facing the bottom end of the incurved part 40 of the hole 36 of the first part 30. The center distance between the holes 42, 44 is substantially equal to the abovementioned radius R. The hole 42 thus ensures the fluidic communication between the hole 34 and the port 22, and the hole 44 ensures the fluidic communication between the hole 36 and the port 24.

The part 32 comprises, on its face oriented toward the expansion valve 26, two protruding cylindrical bushings 46, which surround the corresponding ends of the holes 42, 44. These bushings 46 are intended to be inserted into the ports 22, 24 of the expansion valve 26, to facilitate the positioning and mounting thereof.

The part 32 further comprises, on this same face, two tapped holes 48 which are intended to receive fixing screws (not represented) for the expansion valve 26, the expansion valve comprising two orifices 50 for the passage of these screws.

When the part 32 is applied and fixed, for example by brazing, onto the part 30, the holes 34 and 42 are in fluidic communication and the hole 44 is in fluidic communication with the hole 36 by its bottom end, the rest of this hole 36 being blocked in a seal-tight manner by the covering of the plate 30 by the plate 32.

The slit 36 of the part 30, closed laterally here by the end plate 16 of the exchanger and by the neighboring part 32, thus defines a duct for the fluid between the two non-aligned ports 18, 24. By combining a number of parts together, a passage is therefore formed between said ports without having to involve complex machining or casting operations generally associated with the bulk production of bent ducts.

The expansion valve is mounted on the plate 32 by inserting the bushings 46 of this plate 32 into the ports 32, 24 of the expansion valve, then the above-mentioned screws are mounted in the orifices 50 and screwed into the holes 40 to join together the assembly.

The arrows f1 to f9 represent the path of the fluid from the outlet port 20 of the exchanger to the inlet port 22 of the expansion valve, by passing through the holes 34, 42 of the device and from the outlet port 24 of the expansion valve to the inlet 18 of the exchanger, by passing through the holes 44, 36 of the device. As a variant, this path could be reversed.

In the exemplary embodiment of FIGS. 1 and 2, the expansion valve 20 is in the vertical position. In the variants represented in FIGS. 3 and 4, it is in the inclined position. In these variants, the part 30 is identical to that described previously and thus constitutes a standard part that can be used for a number of embodiments of the invention.

In the variant of FIG. 3, the part 32′ differs from the part 32 described above through the position of its hole 44 which is intended, in the assembled position, to be facing the top end of the inclined part of the hole 36 of the part 30. In this case, the plane P2 of orientation of the expansion valve in which the axes of the holes 42, 44 of the part 32′ extend, is inclined, here by an angle of approximately 45′. In the assembly position, the peripheral edges of the parts 30, 32′ are substantially aligned with one another.

The embodiments of FIGS. 2 and 3 show that a number of different parts 32, 32′ references can be associated with a single reference of a so-called standard part 30.

In the variant of FIG. 4, the part 32 is identical to the part 32 of FIGS. 1 and 2 but is positioned differently in relation to the part 30. The part 32 has undergone a rotation of 45° about the axis A such that its hole 44 is facing the top end of the inclined part of the hole 36 of the part 30.

The embodiments of FIGS. 2 and 4 show that two standard parts 30, 32 can be used to produce a coupling of the exchanger to an expansion valve having any orientation, so long as the second part 32 laterally closes the hole 36.

FIGS. 5 and 6 represent other variant embodiments of the coupling device according to the invention, in which the first part 130, 130′ is formed by a stamped sheet, which has a substantially rectangular outline.

The part 130 of FIG. 5 comprises two zones 152, 154 indented by stamping. The bottoms of these zones 152, 154 are substantially flat and extend in a plane parallel to and at a distance from the plane of the sheet. The first hole 134 is formed in the bottom of the first zone 152 and has a substantially circular outline. The second hole 136 is L-shaped comparable to the shape of the abovementioned hole 36, and is formed in the bottom of the second zone which is also generally L-shaped.

The holes 134, 136 can be formed during the stamping operation or thereafter.

The second part 132 of FIG. 5 differs from the part of FIG. 2 essentially in that it further comprises, on its face oriented toward the first part 130, two protruding cylindrical bushings 155 which surround the corresponding ends of the holes 142, 144 of the part 132. The bushings 156 are intended to be inserted into the holes 134, 136 of the first part 130, to facilitate the positioning and mounting thereof. The bushing 156 of the hole 142 is intended to be inserted into the hole 14, and the bushing 156 of the hole 144 is intended to be inserted into the bottom end of the incurved part of the hole 136, such that the expansion valve, intended to be fixed onto the part 132 has a vertical position.

For that, the hole 134 has a diameter slightly greater than the outer diameter of the bushing 156 of the hole 142, and the bottom end of the incurved part of the hole 136 has a transverse dimension slightly greater than the outer diameter of the bushing 156 of the hole 144.

The second part 132 is configured to laterally close the hole 136.

The part 130′ of FIG. 6 differs from the part 130 of FIG. 5 that the hole 136′ formed in the bottom of the zone 154 has a circular outline and is situated at the level of the top and of the incurved part of the hole 136 of FIG. 5. This hole 136′ has a diameter slightly greater than that of the bushing 156. The part 132 of FIG. 6 is identical to that of FIG. 5, except that it will be able to have a reduced extension because its function is no longer to laterally close the duct linking the port 18 to the orifice 136′, said duct being here laterally closed by the bottom of the stamped part, on the side of said second part 132.

The parts 130, 132 and 130′, 132 can also be fixed together and to the exchanger by brazing, notably when brazing the different parts of the exchanger. 

1. A device for coupling a heat exchanger to an expansion valve for a vehicle, said exchanger and said expansion valve being provided with fluid inlet/outlet ports, at least one of the ports of the expansion valve not being aligned with one of the ports of the exchanger, said device comprising: a first part configured to be joined and fixed to the exchanger, said first part defining, with at least one neighboring part, a first fluid passage intended to couple said non-aligned ports, said neighboring part being chosen from a second part of said device, said exchanger and/or said expansion valve.
 2. The device as claimed in claim 1, wherein: said first part is intended to be pressed fiat onto the exchanger and comprises through holes which cooperate respectively with the ports of the exchanger, and said second part is intended to be pressed flat onto the first part and comprises two through holes which cooperate respectively with the ports of the expansion valve, the through holes of the first and second parts being in fluidic communication to define said first passage as well as a second passage intended to couple the other ports of the exchanger.
 3. The device as claimed in claim 2, in which the through holes of the first part are formed respectively by an opening or slit of elongate form, defining, with said exchanger and/or said second part, said first passage, and by an orifice, defining said second passage.
 4. The device as claimed in claim 3, in which at least a part of the slit has an incurved form about an axis of the orifice of the first part.
 5. The device as claimed in claim 4, in which the incurved part of the slit has a radius of curvature, taken substantially at the middle of the slit, which is substantially equal to a center distance between the through holes of the second part.
 6. The device as claimed in claim 4, in which the slit comprises a rectilinear part of which one end is linked to the incurved part of the slit and of which the opposite end is intended to cooperate with a port of the exchanger.
 7. The device as claimed in claim 4, in which one of the through holes of the second part emerges in the incurved part of the slit of the first part.
 8. The device as claimed in claim 1, in which the first part is formed by a plate or a sheet.
 9. The device as claimed in claim 8, in which the sheet is stamped, the sheet comprising at least two indented zones at the bottom of which the holes are formed by drilling.
 10. The device as claimed in claim 2, wherein the second part is formed by a metal block, and the through holes are formed by orifices.
 11. The device as claimed in claim 1, comprising tubular bushings into which some of the holes of the second part emerge.
 12. The device as claimed in claim 11, in which some of said tubular bushings protrude on a face of the second part, which is situated on the side opposite the first part, and are intended to be inserted into the ports of the expansion valve.
 13. The device as claimed in claim 11, in which some of said tubular bushings protrude on a face of the second part, which is situated on the side of the first part, and are inserted into the holes of this first part.
 14. An assembly comprising: a heat exchanger; an expansion valve; and a coupling device as claimed in claim
 1. 15. A method for mounting a device as claimed in claim 1, in which the part or parts are pressed flat and fixed onto one another and/or between said exchanger and said expansion valve, depending on the desired angular position of the expansion valve.
 16. The device of claim 1, wherein the heat exchanger is an evaporator.
 17. The assembly of claim 14, wherein the heat exchanger is an evaporator. 